Corrugated paper board machine with means for forming a crown on a corrugating roll



P 1970 R K. 'SONNICHSEN 3,527,638

CORRUGATED PAPER iBOARD MACHINE WITH MEANS FOR FORMING A CROWN ON A GORRUGATING ROLL Filed Sept. 20. 1967 4 Sheets-Sheet 1 Fig.1.

- INVENTOR JM/dmwuam/ @%M P 1970 R. K. SONNICHSEN 3,527,638

CORRUGATED PAPER BOARD MACHINE WITH MEANS FOR FORMING A CROWN ON A CORRUGATING ROLL Filed Sept. 20, 1967 4 meets-Sheet 2 p 8, 1970' R. K. SONNICHSEN 3,527,638

CORRUGATED PAPER BOARD MACHINE WITH MEANS FOR FORMING A CROWN ON A CORRUGATING ROLL Filed Sept. 20, 1967 4 Sheets-Sheet 5 Fig. 6.

Sept; 1970 R K. SONNICHSEN 3,527,638

CORRUGATED PAPER iBOARD MACHINE WITH MEANS FOR FORMING A CROWN ON A CORRUGATING ROLL Filed Sept. 20, 1967 4 Sheets-Sheet 4 Fig.7

United States Patent Office 3,527,638 Patented Sept. 8, 1970 3,527,638 CORRUGATED PAPER BOARD MACHINE WITH MEANS FOR FORMING A CROWN ON A COR- RUGATING ROLL Rolf Karl Sonnichsen, Wedel, Holstein, Germany, as-

signor to Maschinenfabrik Werner H. K. Peters GmbH., Hambnrg-Bahrenfeld, Germany Filed Sept. 20, 1967, Ser. No. 669,108 Int. Cl. B31f 1/20, 1/22, 1/26 US. Cl. 156-596 6 Claims ABSTRACT OF THE DISCLOSURE A corrugated paper board machine with a plurality of rolls cooperating with each other and pressed against one another, at least one of said rolls being provided with a crown, for the production of single faced corrugated paper pasted on one side. According to the invention, this crowned roll is formed by pre-bending at least one of said rolls transversely to the axis thereof.

BACKGROUND OF THE INVENTION The rolls employed an corrugated paper board machines are in general more or less provided with a crown depending on the contact pressure, in order to exert pressure on the material to be processed, for example paper or the like during the embossing operation.

Up to now, the corrugating of the corrugated web of corrugated paper has been effected, for example, by passing the paper between two rolls, the so-called corrugating rolls, said rolls being provided on the outside periphery thereof with an axially extending tooth-like corrugation so that upon rotation of these rolls the paper disposed therebetween assumes the desired shape. For this purpose, it is necessary that a certain pressure is generated between the rolls and the paper. The necessary pressure is governed, in particular, by the type of paper being processed and the processing speed. A crown of a roll is understood to be the convex form in an axial direction by which the roll deviates from the cylindrical shape. The deflection of the rolls generated by the pressure is compensated for by the crown in such a manner that a uniform line pressure is effective on the paper over the entire width thereof. The crown may be distributed on both rolls or may also be provided only on one of the two rolls, the other roll then being cylindrical.

With this previous design of the corrugating rolls, and when processing widely differing sorts of paper, it is a prerequisite that several of these very expensive corrugated pairs of rolls with different crowns must be available, which are then fitted in the machine as required in order to obtain optimum results. These rolls are not only expensive but the change to be effected in the machine to fit a set of corrugated rolls provided with another crown takes a considerable amount of time.

SUMMARY OF THE INVENTION To overcome these disadvantages, in accordance with the invention, one or both rolls are pre-bent by bending moments engaging at the ends of the rolls in such a manner that a bending line in correspondence with the crown is generated which then during the contact pressing operation again becomes effective to exert a uniform pressure on the paper.

The thus created bending line is variable by changing the bending moments and thus may be adapted to the respective type of paper and to the processing speed. It is possible in this manner to process with one pair of rolls a much wider range of types of paper so that a smaller number of pairs of rolls need to be kept in store than before. In this connection it is to be noted that the rolls may be cylindrical or also provided with a certain precrown, in order to keep the forces necessary to generate the bending moments low in optimum limits. The forces for the bending moments may be generated pneumatically, hydraulically or mechanically.

The forces necessary for the generation of the bending line are suitably controlled electrically, pneumatically, hydraulically or mechanically in such a manner that a bending line results which corresponds to the necessary line pressure.

The invention relates, however, not only to the deflection of at least one of the corrugating rolls for the purpose of generating a bending line with a crown effect but also to the press roll of such a corrugated paper board machine. The purpose of this machine, as is well known, not only lies in the shaping of a paper web but, in this operation, it is intended also to glue the outer points of the already corrugated paper web lying on the one corrugating roll, and paste it to another paper web, the so-called covering web, under the pressure of a smooth roll, the so-called press roll. This pressure, in many cases, calls for a crown on the press roll.

In accordance with the invention, instead of such a permanent crown, the press roll is pre-bent by means of an outside auxiliary power, into a bending line corresponding to the crown, said bending line being effective to exert under the influence of the contact pressure, a uniform line pressure on the paper over the entire width thereof.

The pressure necessary for the pasting process, contrary to the coining pressure by which the corrugating rolls are pressed against one another, is constant within wide limits.

In practice, it has been found that with types of paper requiring a high coining pressure and thus a large crown on the corrugating rolls, the lower corrugating roll is likewise considerably deflected so that the crown of the press roll cooperating with the lower corrugating roll must be small or even equal to zero, in order to generate uniform pressures over the working width between the lower corrugating roll and the press roll. However, with types of paper requiring low contact pressure values, the opposite comes true: the corrugating roll crown must then be small or equal to zero, while the press roll crown must be considerable. The deflection of the press roll for the generation of a crown effect could likewise be effected by bending moments same as is the case with the corrugating rolls which are engaging at the ends of the press roll and especially at the journals thereof. As the press roll, however, has a smooth surface, here, the deflection may be effected by means of a supporting roll pressing against the press roll about in the center thereof.

In principle, such a solution is to be preferred in connection with the press roll. It is possible also in connection with the corrugating rolls. But here it is recommended, however, to exert the bending moment on the journals of the corrugating roll in order to generate the desired bending line.

Further improvements and suitable developments of the invention are explained in the enclosed drawing which shows one embodiment of the invention in a schematic representation.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows the pair of rolls of a corrugating paper machine in the unloaded condition, with one roll being provided with a known crown,

FIG. 2 shows the pair of rolls of FIG. 1 in a loaded condition,

FIG. 3 shows the pair of rolls of a corrugated paper machine designed in accordance with the invention, in the unloaded condition,

FIG. 4 shows the pair of rolls according to FIG. 3 in the loaded condition,

FIG. 5 is a schematic cross sectional view of the machine designed in accordance with the invention for the production of one-side corrugated paper on an enlarged scale,

FIG. 6 is a transverse view of the machine as shown in FIG. 5 showing all the components essential to carry out the invention,

FIG. 7 shows a sectional view taken on line A-B of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The two rolls of FIGS. 1 and 2 are referenced 18 and 19. The roll 18 is rigidly supported for rotation in the bearings 20 and is driven in a known manner. It is formed cylindrically in the example of embodiment.

The roller 19 is supported for transverse movement in a manner not shown in more detail. Said roll 19 is provided with a crown in the known manner such that it has a maximum diameter D in the center thereof which decreases towards both sides in a uniform convex curve to the diameters d.

It is possible to exert contact pressure forces F on the journals of the transversely movable roll 19 by means of auxiliary devices, not shown, in order to load the roll and press the roll 19 against the roll 18. When exerting these contact pressure forces, the roll will be bent under their influence in the longitudinal direction in such a manner that a uniform line pressure is eflective on the paper web 24 running between the two rolls.

In FIG. 3, a rigidly supported positively driven roll 21 cooperates with a transversely movable roll 22. This roll is pre-bent in its unloaded condition by a bending moment. In accordance with FIG. 3, bending moments are engaging on the journals 23 of the roll 22, which result from the forces F. The roll may have the same diameter D. However, it is also possible to provide the roll with a pre-crown in such a manner that the diameter in the center is not D but D+AD, so that the bending moments necessary to generate the desired bending line become smaller.

FIG. 4 shows the pair of rolls 21 and 22 in a loaded condition, the contact pressure forces F being additionally effective on the journals 23 of the transversely movable roll 22, in order to press the roll 22 against the rigidly supported roll 21. The pre-bent roller 22 is bent by these contact pressure forces F in such a manner that a uniform line pressure becomes effective again on the paper web 24 over the entire width thereof.

In accordance with FIGS. 5 and 6, in a corrugated paper machine for the production of a one-side pasted corrugated paper, there is present one upper corrugated roll 2, the lower corrugated roll 3 and a press roll 4. The axes of all the three rolls are arranged in one end the same as will be seen from FIGS. 5 and 6.

The corrugated paper machine comprises two side stands 1, which are rigidly interconnected in a manner not shown in more detail. The journals 39 of the lower corrugated roll 3 are rigidly supported for rotation in the side stand with the aid of bearing lids 6. 25 designates a shaft driven from outside which drives the lower corrugated roll 3 via a universal joint 26.

The journals of the upper corrugated roll 2 are designated 27. Each journal is supported in two axially spaced bearing levers 5 each pivotally supported about a journal 28 fastened in the side stand 1. Journal 27 and thus the upper corrugated roll 2 are therefore capable of movement transversely of the lower corrugated roll 3, the circle through which the axis of the upper corrugated roll 2 may be pivoted, forming approximately a tangent to the plane connecting the axis of the upper corrugated roll 2 and the lower corrugated roll 3. Auxiliary hydraulic power devices 11, 12 are engaging at both bearing levers 5 of the upper corrugated roll 2, the axis of force thereof being disposed approximately in the plane in which the axes of the upper and lower corrugated rolls are disposed. In the example of embodiment, both auxiliary power devices consist of a piston and cylinder arrangement, the pistons 28 of which are pivotally engaging at the bearing lever 5 and the cylinder 29 of which are pivotally engaging at the side stand 1 or a cross beam 30 rigidly connected with the side stand 1.

Both auxiliary power devices 11, 12 are capable of being biased with a pressure medium from both sides, for instance, with a hydraulic fluid or compressed air. It is possible by a corresponding bias on the four auxiliary power devices 11, 12 on both sides of the upper corrugated roll 2 to impart to the upper corrugated roll 2 not only any desired bending line but also to press the upper corrugated roll against the lower rigidly supported corrugated roll 3 with any pressure that may be desired. The upper corrugated roll will be diven by the engagement of the corrugation thereof with the corrugation of the lower corrugated roll 3.

The press roll 4 is likewise supported for transverse movement. For this purpose the journals 31 thereof are supported in the bearing levers 7, which are pivotally supported about the journals 32 fastened in the side stand 1 of the machine. The pivoting circle of the axis of the press roll touches approximately the plane through which the axes of the press roll 4 and the two corrugated rolls 2, 3 extend.

A shaft 33 positively driven from otuside drives the press roll 4 via a universal joint 34.

The press roll 4 is pressed against the lower corrugated roll 3 by means of an auxiliary force device 13 which in the example of embodiment is likewise designed in the form of a piston and cylinder or servomotor arrangement. The cylinder 35 of each of the two auxiliary power devices 13 engages pivotally at a side stand 1, while the piston 36 pivotally engages at a bearing lever 7. The line of force of this auxiliary power device thus lies approximately in the plane in which the axes of the three rolls 2, 3, 4 are disposed.

The press roll may likewise have imparted thereto an arched or arcuate deflection in order to obtain a crown effect. For this purpose, a supporting roller 8 is effective on the press roll 4 symmetrically with respect to the center line 38 of the machine, which may be loaded by means of an auxiliary power device 14. This auxiliary power device 14 is likewise provided in the form of an auxiliary power device 'with a cylinder 40 and a piston 41 capable of being biased from both sides.

The supporting roll 8 is rotatably supported in two bearing levers 9 which are pivotally supported about a traverse of cross shaft 10 extending transversely over the machine and fastened at both side stands 1 in a manner not shown in more detail. At the free end of the two bearing levers 9, the piston 41 of the auxiliary power device 14 pivotally engages, the cylinder 40 of said piston and cylinder arrangement pivotally engaging at a cross shaft 42 extending across the machine between the two side stands 1.

In addition, an adjustable press roll stop 15 has been provided, which cooperates with bearing levers 7 and with the aid of which it is possible to adjust the extent of the contact pressure of the press roll 4 against the lower corrugated roll 3.

The one-side pasted corrugated paper which is to be produced by the machine, is formed of the corrugated web 17 and the covering web 16. The corrugated web 17 has a corrugation imparted thereto by being passed between the two corrugated rolls 2, 3. 'I'hereupon, the peaks disposed outside of the corrugations are provided with a glue applied thereto by means of a glue applicator roll 43.

The applicator roll dips in a glue bath 44 in a manner known per se and cooperates with a scraper roll 45' the purpose of which is above all to uniformly distribute the glue on the applicator roll possibly uniformly before being applied to the corrugations, Thereupon, the covering web 16 is applied to the one side of the corrugated web 17 by means of the press roll 4. Simultaneously, the one-side corrugated paper produced in this manner is pressed by exerting a transverse force on the corrugations of the corrugated web 17. The directions of rotation of the individual rolls 2, 3, 4, 43 and 45 and the directions of movement of the two webs 16 and 17 are shown in FIG. 5.

The upper corrugated roll 2 is pressed against the lower corrugated roll by the force F while the press roll 4 is pressed against the lower corrugated roll by the force F What I claim is:

1. Apparatus for producing paper products utilizing a pair of elongated rolls between which a paper web is passed characterized by its, ability to maintain uniform contact line pressure throughout the entire width of the rolls comprising, in combination, a frame, a first roll having a peripheral surface including a central region and an axis of rotation rotatably mounted on said frame, a second roll having a peripheral surface including a central region, first and second ends, and an axis of rotation, mounting means rotatably mounting said second roll on said frame wherein the axis thereof is generally parallel to said axis of said first roll and said second roll axis is movable toward and away from the axis of said first roll, said mounting means comprising a pair of independent adjustment means at each end of said second roll, each adjustment means including relatively movable elements movable toward and away from said first roll axis, said adjustment means of each pair being axially spaced with respect to each other along the axis of said second roll, said adjustment means of each pair being separately operable to predetermine the spacing between said roll axes and impose a bending force upon said second roll to deflect said central region of said second roll toward said first roll and thereby produce a uniform contact line pressure between said rolls upon a paper product web passing therebetween.

2. Apparatus for producing paper products as in claim 1 wherein said independent adjustment means comprise separate expansible motors and said movable elements of each adjustment means comprises a cylinder and a piston slidably received therein.

3. Apparatus for producing paper products as in claim 1 wherein at least one of said rolls peripheral surface includes a crown defined in the central region thereof.

4. Apparatus for producing paper products as in claim 1, a third roll having a central region and rotatably mounted upon said frame in engagement with said first roll and generally parallel thereto engaging said first roll surface in diametrically opposed relation to the engagement between said first and second rolls, bearing means supporting said third roll in said frame, and adjustable means supporting said bearing means for movement toward and away from said first roll axis.

5. Apparatus for producing paper products as in claim 4, a supporting roll mounted upon said frame engaging said third roll central region in diametrically opposed relation to the engagement between said first and third rolls, and loading means connected to said supporting roll for biasing said supporting roll against said third roll and deflecting said third roll central region toward said first roll to define a crown in the central region of said third roll adjacent said first roll.

6. Apparatus for producing paper products as in claim 5 wherein said loading means comprises an expansible motor.

References Cited UNITED STATES PATENTS 1,960,677 5/1934 List 156-596 2,310,421 2/ 1943 Greenwood 156-596 2,542,230 2/1951 Bruker 156-596 2,687,165 8/1954 Hollis 156-596 2,960,144 11/1960 Graf 156-596 FOREIGN PATENTS 633,545 12/ 1949 Great Britain. 767,301 1/ 1957 Great Britain.

BENJAMIN A. BORCHELT, Primary Examiner C. T. JORDAN, Assistant Examiner U.S. Cl. X.R. 156-205, 470 

